首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2388篇
  免费   71篇
  国内免费   34篇
管理学   63篇
民族学   22篇
人才学   1篇
人口学   91篇
丛书文集   188篇
理论方法论   174篇
综合类   1245篇
社会学   640篇
统计学   69篇
  2024年   10篇
  2023年   24篇
  2022年   27篇
  2021年   27篇
  2020年   71篇
  2019年   49篇
  2018年   69篇
  2017年   90篇
  2016年   55篇
  2015年   75篇
  2014年   119篇
  2013年   380篇
  2012年   128篇
  2011年   109篇
  2010年   106篇
  2009年   114篇
  2008年   136篇
  2007年   140篇
  2006年   126篇
  2005年   114篇
  2004年   103篇
  2003年   103篇
  2002年   86篇
  2001年   93篇
  2000年   38篇
  1999年   30篇
  1998年   15篇
  1997年   14篇
  1996年   17篇
  1995年   1篇
  1994年   8篇
  1993年   7篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1984年   1篇
  1981年   1篇
排序方式: 共有2493条查询结果,搜索用时 15 毫秒
91.
Direct applications of remote sensing thermal infrared (TIR) data in landscape ecological research are rare due to limitations in the sensors, calibration, and difficulty in interpretation. Currently there is a general lack of methodology for examining the relationship between land surface temperatures (LST) derived from TIR data and landscape patterns extracted from optical sensors. A separation of landscapes into values directly related to their scale and signature is a key step. In this study, a Landsat ETM+ image of Indianapolis, Unites States, acquired on June 22, 2000, was spectrally unmixed (using spectral mixture analysis, SMA) into fraction endmembers of green vegetation, soil, high albedo, and low albedo. Impervious surface was then computed from the high and low albedo images. A hybrid classification procedure was developed to classify the fraction images into seven land use and land cover (LULC) classes. Using the fractional images, the landscape composition and pattern were examined. Next, pixel-based LST measurements were correlated with the landscape fractional components to investigate LULC based relationships between LST and impervious surface and green vegetation fractions. An examination of the relationship between the LULC and LST maps with landscape metrics was finally conducted to deepen understanding of their interactions. Results indicate that SMA-derived fraction images were effective for quantifying the urban morphology and for providing reliable measurements of biophysical variables. LST was found to be positively correlated with impervious surface fraction but negatively correlated with green vegetation fraction. Each temperature zone was associated with a dominant LULC category. Further research should be directed to the theoretical and applied implications of describing such relationships between LULC patterns and urban thermal conditions.
Dengsheng LuEmail:
  相似文献   
92.
This study examines the association between individuals' educational assortative mating and time spent on child care and housework. Focus is put on hypogamous couples, or couples in which wives have more education than their husbands. Relative resources and gender revolution frameworks are considered as contexts to explain why hypogamous couples may share their time differently than other couples. A series of ordinary least squares regressions with population and sampling weights are employed using American Time Use Survey data from 2003 to 2018. Three, separate analyses using relative education, gender, and all educational pairings as the independent variables of interest are presented with child care and housework as the dependent variables. The current findings show that men in hypogamous marriages perform about 10 min more of child care per day on average than their peers in hypergamous and homogamous marriages, and that this comes primarily from basic care activities. This accounts for approximately 43% of the difference between men and women in the average amount of time spent on child care. No clear pattern of significance is apparent comparing individuals’ time spent on housework by relative education, suggesting that housework and child care have evolved differently in the context of gendered domestic responsibilities. Men in hypogamous marriages are more egalitarian in their sharing of child care. However, this is only true for couples in which men have at least a high school diploma and women are highly educated.  相似文献   
93.
Do people think individuals with Substance Use Disorder (SUD) have freewill? How does addiction science inform views on the issue? We distinguish between two senses of freewill: 1) libertarian freewill , in which freedom turns on a particular metaphysical conception of action (sometimes operationalized as “could have done otherwise”), and 2) compatibilist freewill , in which freedom depends on the relation between the actor's psychology and her actions (e.g., “was the act what she wanted to do?”). We argue that, in different ways, scientific accounts can impact conceived freewill by linking addictive behavior to mechanisms that observers view as peripheral to the actor ( motivation modularity) . While a variety of impacts on conceived compatibilist freewill are plausible, we argue that contemporary addiction science has no direct bearing on conceived libertarian freewill. Addiction science may, however, indirectly impact conceived libertarian freewill by priming an explanatory framework in which intention is superfluous (especially materialism).  相似文献   
94.
This study explored the case of a former addict, focusing on his existential self‐interpretation and identity transformation process. This study began from the question of whether philosophical processes related to existential self‐interpretation could lead to the formation of the concept of bottoming out and of identity transformation. To answer this question, the study analyzed the case of a male in his mid‐forties who was addicted to drugs for approximately 30 years and has only recently maintained abstinence. The study used the phenomenological approach to determine the meaning drugs held for him in each stage, and what drug‐related identity he had in each stage. Further, this study identified the integrative implications of these meanings in terms of existential self‐interpretation and identity transformation. The four different identities the man identified for the four stages of his life were juvenile delinquent, gang member, half‐gangster, and breadwinner, and the associated meanings drugs had for him during each period were “glue,” “filthy,” “leeches,” and “abstinence,” respectively. Finally, this study elucidated the integration of these meanings through the hermeneutic circle, identified the social welfare implications of the findings, and developed educational recommendations.  相似文献   
95.
ABSTRACT

The aim of this study was to explore the effectiveness of Methadone Maintenance Treatment (MMT) from the perspective of drug users and their families. For this qualitative content analysis study, 15 participants were selected via purposive sampling. Data collection was done using deep and semi-structured interviews, which were then analyzed. The results showed that MMT can bring favorable impacts into the patients’ lives and help them with the process of treatment and rehabilitation despite the medical side effects.  相似文献   
96.
Multisite evaluation has been cited as a strategy for building knowledge about a program's success and enhancing evaluation capacity and evaluation use. Even so, the extent to which data from these efforts are made available to individual project participants varies. This article describes a community-created multisite evaluation that was designed to overcome this limitation. Based on the negotiated centralized evaluation model and implemented within the context of a community of practice, the EvalFest community-created multisite evaluation has used shared measures to collect data from 30,000 participants from partner sites across the community over three years. This article describes the design characteristics of the community-created multisite approach, and presents results related to partners’ evaluation use that demonstrate the early success of this method. We conclude by considering how this strategy might be applied to other sectors.  相似文献   
97.
Objective: The objective of this study was to understand substance use patterns of alcohol, marijuana, and simultaneous alcohol and marijuana (SAM) use among 2- and 4-year college students. Participants: Participants were 526 young adults aged 18–23 (n?=?355 4-year students; n?=?171 2-year students) recruited from February 2015 to January 2016 who were participating in a larger longitudinal study. Methods: Latent class analysis (LCA) was used to identify past-month classes of alcohol, marijuana, and SAM use. Results: Among both 2- and 4-year students, a four-class solution yielded the best-fitting model, with 2-year classes tending to include greater marijuana use and less alcohol use and 4-year classes tending to include heavy alcohol use. Demographic characteristics were largely similar across classes. Conclusions: Classes of alcohol, marijuana, and SAM use differed by education status. Screening and prevention efforts for 4-year students may need to be tailored for the needs of 2-year students.  相似文献   
98.
Studies have mostly examined mental health service use of older Asian immigrant combining all Asian Americans into one group whereas immigration backgrounds and socioeconomic status of each Asian minority group are different. Therefore, this study aimed to identify predictors of mental health service use within specific ethnic groups among older Asian adults focusing on Chinese, Japanese, Korean, Filipino, and Vietnamese in California. The Behavioral Model for Vulnerable Populations (BMVP) is used to guide the secondary data analysis of a sample of 3,453 older Asian immigrants from the California Health Interview Survey (CHIS). Logistic and linear regression analyses are performed to examine predictors of mental health service use and the frequency of mental health service use, respectively. As results, mental health‐seeking patterns differ by ethnicity within the older Asian immigrant sample, not being married (Korean), higher levels of acculturation (Filipino), lower levels of neighborhood cohesion (Korean and Vietnamese), higher levels of perceived safety (Korean) and lower levels of perceived safety (Vietnamese), higher levels of mental distress (Korean and Filipino), and having perceived need (all) were related to more visits for mental health services. The study findings highlight the necessity of cultural competency services and programs for each Asian ethnicity.  相似文献   
99.
100.
This study examined the characteristics of youth with different types of purpose in life, as well as the associations between adolescents’ life satisfaction, purpose in life, meaning in life, social support, and problematic digital use. The sample included 193 participants aged 14–18 who completed self-report questionnaires on life satisfaction, purpose in life, meaning in life, social support, and problematic digital use. The following purpose in life clusters were found: (1) other-oriented goals (n?=?33); (2) self-oriented goals (n?=?42); and (3) both other- and self-oriented goals (n?=?107). Adolescents with both self- and other-oriented goals had significantly higher life satisfaction, meaning in life, and social support compared to the other groups. Meaning in life and greater support from parents and teachers were significantly associated with greater life satisfaction. In addition, having other-oriented goals was associated with lower life satisfaction. Finally, support from parents (p?=?0.05) mediated the association between problematic digital use and life satisfaction. Findings are discussed in light of previous research and the theoretical and practical implications are examined.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号